nvme: generalize the nvme_multi_css check in nvme_scan_ns

Check for multiple command set support early on an error out if is
not supported when a !NVM command set namespace is found.  This
prepares for adding command set independent passthrough support.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJavier González <javier.gonz@samsung.com>
Reviewed-by: NJoel Granados <j.granados@samsung.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NKanchan Joshi <joshi.k@samsung.com>
Reviewed-by: NChaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

drivers/nvme/host/core.c

@@ -4294,6 +4294,12 @@ static void nvme_scan_ns(struct nvme_ctrl *ctrl, unsigned nsid)
 	if (nvme_identify_ns_descs(ctrl, nsid, &ids))
 		return;
 
+	if (ids.csi != NVME_CSI_NVM && !nvme_multi_css(ctrl)) {
+		dev_warn(ctrl->device,
+			"command set not reported for nsid: %d\n", nsid);
+		return;
+	}
+
 	/*
 	 * Check if the namespace is ready.  If not ignore it, we will get an
 	 * AEN once it becomes ready and restart the scan.
@@ -4325,12 +4331,6 @@ static void nvme_scan_ns(struct nvme_ctrl *ctrl, unsigned nsid)
 				nsid);
 			break;
 		}
-		if (!nvme_multi_css(ctrl)) {
-			dev_warn(ctrl->device,
-				"command set not reported for nsid: %d\n",
-				nsid);
-			break;
-		}
 		nvme_alloc_ns(ctrl, nsid, &ids);
 		break;
 	default: